Re: The --password and clumsy users issue

Oh, I was playing about with this earlier, but didn't get all that far:

I go this far in svn.c (has breakpoint marker in it)

[[[
 int

  main(int argc, char **argv)

  {

    apr_pool_t *pool;

    int exit_code = EXIT_SUCCESS;

    svn_error_t *err;

    const char **argv_org;

    /* Initialize the app. */

    if (svn_cmdline_init("svn", stderr) != EXIT_SUCCESS)

      return EXIT_FAILURE;

    /* Create our top-level pool. Use a separate mutexless allocator,

     * given this application is single threaded.

     */

    pool = apr_allocator_owner_get(svn_pool_create_allocator(FALSE));

    {
      int i;

      argv_org = apr_palloc(pool, sizeof(argv));

B for(i = 0; i < argc; i++)

        {

          argv_org[i] = apr_pstrdup(pool, argv[i]);

          if (i > 2 && !strcmp(argv[i-1],"--password"))

            {

              argv[i-1] = "#####\0";

            }

          if (i > 2 && !strcmp(argv[i-1],"--username"))

            {

              argv[i-1] = "#####\0";

            }

        }

    }
]]]

it compiles and runs and in gdb the vars do change, but the compiler isn't
happy:
subversion/svn/svn.c: In function 'main':

subversion/svn/svn.c:3048:23: warning: assignment discards 'const'
qualifier from pointer target type [enable\
d by default]

             argv[i-1] = "#####\0";

                       ^

subversion/svn/svn.c:3052:23: warning: assignment discards 'const'
qualifier from pointer target type [enable\
d by default]

             argv[i-1] = "#####\0";

At breakpoint B, gdb gives me:

(gdb) p argv

$1 = (char **) 0x7fffffffe468

(gdb) p argv[1]

$2 = 0x7fffffffe81e "svn"

(gdb) p argv[2]

$3 = 0x7fffffffe822 "help"

(gdb) p argv[3]

$4 = 0x4438b3 "#####"

(gdb)

So it def. does change it.

On Fri, Jul 4, 2014 at 12:40 AM, Ben Reser <ben_at_reser.org> wrote:

> On 7/3/14 4:23 PM, Gabriela Gibson wrote:
> > Could that be because of the libtool svn-lt script that sits in the
> middle?
> > Because in gdb it does change, but not in ps.
>
> No because I wasn't even doing anything with Subversion yet let alone
> libtool.
> It was just a very basic C program with nothing more than a main. It's
> probably because the argv array belongs to the process itself and then it
> points to memory that the kernel owns (or at least watches). I'm not sure
> on
> all the details of how the kernel starts the binary and passes in the
> arguments.
>
> I've attached the example I was working with that didn't make it to this
> list
> already.
>
>

-- 
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